This invention relates generally to vehicles and more particularly to vehicles convertible from railway to highway use.
Various proposals have been made for vehicles which can be converted between railway and highway use. These vehicles have attempted to use the same number of axles during highway use as during railway use to support the vehicle. Since the permissible axle loading during highway use is much less than the permissible axle loading during railway use, the maximum permissible load which could be carried in these prior art convertible vehicles was limited by the permissible axle loading for highway use. As a result, the number of prior art convertible vehicles required to carry a given payload was significantly increased as compared to the number of standard railway cars required to carry the same payload. This increased number of convertible vehicles served to increase the overall capital cost of such vehicles for a particular payload, increased the number of highway truck tractors required for highway transport and increased the operational costs associated with the use of such vehicles. Because of these problems, such prior art vehicles have not found widespread use.